Machine for correcting printing plates



April 13 1926. v 1,580,236

E. ERICKSSON MACHINE FOR CORRECTING PRINTING PLATES Filed Dec. 12 1923 4 Sheets-Shut 1 Bug 4 I'miZEr' 76,55

April 13., 1926. 1,580,236

' E. ERICKSSON MACHINE FOR CORRECTING PRINTING PLATES Filed D c. 12. 1923 4 Sheets-Sheet 2 5/ 4 4 F I L n 17 d a 79 g? 5 f 1 ,0 l f 1 g W i m l H 15 1 L;

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' E. ERICKSSON momma FOR commc'rme PRINTING PLATES 4 She ets-Sheot 5 III VIII Filed Dec. 12

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April 13 1926. T 1,580,236

. E. ERICKSSON MACHINE FOR CORRECTING PRINTING PLATES Filed Dec. 12, 1923 4 Sheets-Sheet 4 Patented Apr. 13, 1926 UNITED STATES EMIL nnroxsson, or CHICAGO, I LIivors,

PA-TENT OFFICE.

ASSIGNOR TO A. FIELD COMPANY, or

on'rcaeo, rnnmorsn ooRPonArIoNor ILLINOIS. t 1

MAoHnvE non oonREcrInfG PRINTING P A ES.

Application filed December T 0 all whom; it may concern 7 Be it known that I, Earn, EnroKssoN, a

citizen of the United States, residing at v Chicago, in the county of Cook and Stateof Illinois, have invented certain new and useful Improvements. in Machines for Correct ing Printing Plates, of which the follo is a specification.

The machine of the present invention is in the form of a'press designed for the purpose of correcting inequalities appearing in the type surface of a printing plate prior to the setting up of the plate in a printing press. Printing plates, after casting and before correction, are ordinarily found to present inequalities in the type surface due to warpingof the metal or similar causes, so that the type surface does not present a true plane, with the result that if a plate of this character be set up "in a printing press against a plain unyieldingbed or plate, and

by providing means acting against the back of the plate in such a way as to permit the inequalities to. register in the back'rather than in the type surface.

The present invention relates to a press of a character which is designed to correct the plates prior to their introduction into the printing press which permits a large number of plates to be corrected in rapid succession, and thereafter distributed for use on various printing presses. I I

The invention consists in the features of construction and combinations of parts hereinafter described and claimed.

In the drawings:

Figure 1 is a front elevation of the machine of the present invention;

Fig. 2 is a section taken on line 2- -2 of Fig. 1; V

Fig. 3 isa section taken on line 33 of s- Fig. l is an enlargcddetail showing one of the removable face plates which furnishes the upper contact surface forthe type plate under correction;

Fig. '5'is a'plan viewpartly broken away,

w ng

'12, 1923. Serial No. esoaa'z.

showing means for effecting in and out reciprocation of one of the supporting plates;

Fig. 6 is'a view taken on line66 of Fig. 5,

Fig. 7- 1s a SGCt-lOllitl view taken at right angles to the above on line 7-7 of Fig. 5;-

Fig. Sis a sectional detail showinga printing plate in position prior to correction with inequalities in its upper face; and

Fig.0 is-a similar view showing the'same plate. after correction with the inequalities transferred tothe back surface.

a base 10 provided with two sets'ofstandards 11 and 12 respectively, the standards 11 comprising the'right hand set being six in number, and the standards 12 comprising the left hand set being four in number. All the standards extend in vertical relation to the base and in parallel relation to one an other and furnish guideways for the vertical reciprocation of a right hand press head '13 and a} left hand press head 14 which are adapted to beraised and lowered by suitable hydraulic or other means which need notbe 1 described in detail. I The right hand. press 13is provided at its corners with, guide lugs 15 which embrace theproximatecorner standards 11, and at interi'nediate points with guide lugs 16 which The machine, as a whole, is mounted upon' en'ibrace the-intermediate standards 11 and slide freely the eon asthe press head is raised and, lowered. Similarly the press head 14 is provided with corner guide lugs 17 four'in nu1nber, whic'h embrace the proximate standards 12. provided on its top withga sliding table plate 18 which is guided between flanges 19 for in andont reciprocation; and tl e press head 14 is provided with a similar table plate 20 guided by flanges 2l and likewise adapted to be moved in and out. Interposed between the two tablesand lllfCOlltfiCt with the adjacent guide flanges-l9 and 21 is a bridge plate 22, the inner edge of'which abuts-against the adjacent inner front standards l1 and 12 and extends forwardly therefrom, which bridge plate is loosely laid against'the flanges 19 and 22, so that either of the press heads may be liftedslightly' and thereby tilt the'abuttingcdge of the bridge plate without displacing the bridge plate from its position intermediate the two press heads.

As shown in Figs. 1

and 2, the flanges The press head 13 is I 19 and 21 extend upwardly from two pair of supporting guide rails 23 which serve to support the bridge plate 2 in constantly proj cted position and also serve as guides for the in and out reciprocations of the two 24: provided with supporting arms 25 whichextend laterally to and are integrally formed with the guide rails 23. The arms and the bracket casting merge into a top plate 26 which bridges the space between the guide rails 23 and furnishes a rugged support for the operating mechanism housed below each of the slidable table plates. Each table is provided near its front edge with a pair of spaced guide bars 27 which afford a guide channel for the reception of a roller 28 which is carried at the front end of a swinging arm 29 mounted at the upper end of a vertical stub shaft 30 which passes through a bearing sleeve 31 forming part of the bracket casting. The arrangement is such that as the stub shaft is rotated in eithe direction the roller 28 riding within the guide channel will move the table back and forth to the desired degree.

The stub shaft 31 has mounted thereon a worm gear 32 which is adapted to receive motion from a worm 33 carried by a shaft 34, which latter is iournaled within a swinging bracket 35. The shaft carries spur gear 36 which meshes with a spur gear 37 on a constantly rotating shaft 33 upon which the swinging bracket is loosely mounted,

so that the bracket may be swung been and forth without unmeshing the gears. When the bracket is swung forwardly by bearing down upon a pivoted lever arm 39, it will bring the worm 33 into mesh with the worm gear 32 and the latter will begin to rotate. The upper end of the bracket 35 is provided with a lugO'which is adapted to engage with a notch 41 in a dog d2 pivoted at its forward end to a pin 4-3 and provided at its intermediate point with a notch 44. The notch 44-. is adapted to occupy a position within the line of movement of either one of two lugs 45 upstanding from the upper face of the worm gear 32. The arrangement is such that when the bracket 35 is swung upwardly by the depression of the lever arm, 39, the lug l0 will be engaged by the notch 41 in the dog, holding the parts in latched relation during a half rotation of the worm gear 32, at which 'ne one of the lugs 45 will have reached a position where it will ride under the notch 4st in the dog, and by engaging the beveled forward end. of the notch lift the dog, thereby disengaging the notch &1 from the lug 40 and permitting the bracket 35 to swing back, unmeshing the transmission'train, and stopping further movement of the table. This will impart a half rotation to the arm 29 which will serve to swing the arm from its extreme forward medial position to its extreme rearward medial position, or vice versa, as the case may be, thereby imparting either an in movement or an out movement to the table plate, depending upon'the position originally occupied.

The press head 13 with its table plate 18 co-acts with a fixedly mounted upper press head 46 provided with a removable face plate 47, which latter is preferably made of hardened steel and constitutes the plane surface against which the type surface of the type plate is corrected. The edges of the face plate engage undercut guide flanges 48 and the plate is provided with a. handle 49 permitting its removal for the purpose of cleaning from time to time. The left hand press head 14- and table plate 20 co-aet with a fixed upper press head 50 which is provided with a removable face plate 51 similar in all respects to that previously described and slidably mounted between undercut guide flanges 02. The two press heads are fixedly mount-ed upon the upper ends of the'standards 11 and 12 respectively; and the ri 'ht hand fixed press head is bored to receive a plurality of gas burners 53, the gas nozzels of which project downwardly so to heat the surface of the face plate 48 which contacts the type plate under correction.

Suitable gas pipe connections are provided for the gas nozzels, but these need not be described in detail. The gas burners 53 connect with a header pipe 5st shown in Fig. 2. The fixed press head 50 is provided with a chamber 50 having entered thereinto an inflow pipe 55 and an outflow pipe 56- adapted to furnish a supply of cold water to the chamber for the purpose of cooling the chamber, the rightha-nd press heads serving to correct the printing plates under heat, and the left hand chamber serving thereafter to cool them before removal from the machine.

The shaft 38 is provided with universal connections 57 which accommodate the up and down movements of the respective presses. The shaft is operated from any suitable source of power, as, for instance, a motor Suitable means for operating either of the hydraulic mechanisms are also provided.

Each table plate is provided with an embossed correction backing for the printing inc mea s-as plate, which backingis shown detail in F igs, 8 and 9, although the precise formof backing may bevaried or modified, it being understoodthatthe form here shown serves merely for purposes of illustration, and that.-

other forms havingsimilar capacities may'be used ln llGi1:i?l1eIG0f. As shown,--the correction backing consists of a base layer 6Q having formed thereon spaced bosses-or pro tuberances' 61 of some yieldable material or composition overlaid with a facing layer 62. The bosses or protuberances'areadapted to yield locally when pressure is applied to correct the printing plate, and being spaced apart from one another are adaptedto distort locally to the degree required to ac commodate varying inequalities in thethickness of the plate.'-* I The correction backing may be afforded either by a material-having elastic properties like rubber which will tend to restore to normal condition after distortion, in which case the same correction backing can be used permanently in the press without frequent renewal; or the backing may be formed of such a-compositionas wi1l=crushdown and deform under pressure after a single "plate'hasbeen-"corrected, in which case the correction backing will be in the form of removable sheets or layers'adaptedfor freqnent substitution.

The correction layer in whatsoever form,

however, has the capacity for-local distor-.

tion, either temporary or permanent-,1 and should preferably provide displacement gaps or spaces to accommodate the local deforma tion due to transference, under compression, of inequalities'in the typ e surface to the back surface, as indicated in Figs. 8 and 9. In use, the mechanisms which control the right and left table plates are operated to bring both of the tables into projected position, and the correction backing layer is positioned in place on the right hand table,'with the type plate resting thereon faced upward.

The press head being in lowered position, as soon as the printing plate'is positioned, the mechanism for controlling the right hand table plate is operated and the table platerwill be moved back into position to bring the type surface immediately below the heated face plate of the right hand press. Thereupon, the right hand hydraulic or other pressure mechanism will be actuated and the right hand press head lifted to bring the type surface into contact with the heated plate. After the type plate has been heated sufiiciently to render it slightly plastic, the pressure is increased to the amount required to level out the type surface and press down the inequalities therein, which inequalities will then appear upon the back surface of the type plate and will cause varying indentations in the correction backing layer, as indicated in Figs. Sand 9, the

varying amount to accommodate the inequalities.

After the-plate has been corrected, the press'head is lowered, and the right hand; table restored "to its initial position which bringslthe two table] plates and the intervenfingbridge plate into plane' alignment, so that the corrected plate still mounted upon the correction backing may he slid overonto the left hand table plate which is then actuated to bring the type plate with its backing into interposed relation to the press heads of the left'hand'press, after which the left hand press head-is raised and the type plate maintai-ned in contact with the cool surface of .b,acking 'layer deforming or 'displacing in the left hand-upper press platefor'a'sufiicient 7 time tocool the, type plate, after which the lefthand table. is restored which completes the operation. In manipulating the type plate, it isnot always necessary to move "the back correction layer withthe type plate since, if desired, each of thetable plates may-= be provided with apermanently at tached correction back layer havingayield- I ing surface,-=ini which case the: type plate is simplyfm'oved across from one'lto the other.

Although the inventionhasbeen described with particularity, it isnot the intention to limit theinvention to. the precise details shown-and described, since, as previously indicated; the formation o'fthe correction backing layer brothers features of the press structure may be modified without departing from the spirit of the invention.

JIfcl'aimf l 1Q In a'machine1for correcting printing plates, the combination of two presses each provided with av fixed upper press head and heatingv one of the fixed press heads, and means for cooling the other fixed press head,

substantially as described.

2. In a machine for correcting printing plates. the combination of two presses each provided with a fixed upperpress head and a'movable lower press head, independent means for actuating each of the lower press heads, a .table plate carried by each of the 7 lower pressheads, guide mountings for each ments thereof into and out of register with the .co-operating fixed press head, a bridge plate located between the table plates, said of said table plates for permitting movetable plates and said bridge plate lying in a continuous plane when both of said table plates are projected and lowered, means for heating one of the fixed press heads, means for cooling the other fixed press head, and a removable face plate for each of the fixed press heads, substantially as described.

3. In a machine for correcting printing plate the combination of two presses each provided with a fixed upper press head and -a movable lower press head, independent means for actuating each of the lower press heads, a table plate carried by each of the lowerpress heads, guide mountings for each of said table plates for permitting movements thereof into and out of register with the co-operating fixed press head, a bridge plate located between the table plates, said table plates and said bridge plate lying in a continuous plane when both of said table plates are projected and lowered, means for heating one of the fixed press heads, means for cooling the other fixed press head, and a correction backing layer mounted upon one of the tables and formed of material adapted to yield locally to inequalities in the surface of the printing plate .being corrected, substantially as described.

l. In a machine for correcting printing plates, the combination of two presses each provided with a fixed upper press and a movable lower press head, independent means for actuating each of the lower press heads, a table plate carried by each of the lower press heads, guide mountings for each of 'said table plates for permitting movements thereof into and out of register with the co-operating fixed press head, a

bridge plate located between the table plates, said table plates and said bridge plate lying in a continuous plane when both of said table plates are projected and lowered, means for heating one of the fixed press heads, means for cooling the other fixed press head, a removable face plate for each of the fixed press heads, and a correction backing layer mounted upon one of the tables and formed of material adapted to yield locally to inequalities in thesurtace of the printing plate being corrected, substantially as described.

In a machine for correcting printing plate, the combination of two presses each provided with a fixed upper press head and a movable lower press head, independent means for actuating each of the lower press heads, a table plate carried by each of the lower press heads, guide mountings for each of said table plates for permitting movements thereof into and out of register with the co-acting fixed press head, a bridge plate located between the table plates, said table plates and said bridge plate lying in a continuous plane when both of said table plates are projected and lowered, means for heating one of the fixed press heads, means for cooling the other fixed press head, and a correction backing layer carried by one of the table plates'and formed of yieldable material configured to present a surface con sisting of bosses and intervening spaces to provide for the variable displacement of the bosses during the correction process, substantially as described. 7

EMIL ERICKSSON. 

